I see fullcalendar provides NPM packages
like npm install --save @fullcalendar/core @fullcalendar/resource-timeline
(See https://fullcalendar.io/docs/plugin-index)
You can follow these steps
https://docs.mendix.com/howto/extensibility/create-a-pluggable-widget-one/
If you need technical expertise, we can connect.